u had the side effects of the drug concerta
.. it is methylphenidate
which is a central nervous system
activator ..so since it was the first time , u had experienced the irritability and jitteriness with more severity ,and even ur knowledge of taking the tablet fr a particular purpose has aggravated the effects..
anyways u can sleep freely as u r ok now and nothing to worry furthe with this dosage u hv taken ..
i suggest u nt to take any such medications without doctor advice
..actually it should b taken only as a medication to some diseases and not generally..
all the best..